import { Operator } from '../Operator';
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import { Subscriber } from '../Subscriber';
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import { async } from '../scheduler/async';
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import { Observable } from '../Observable';
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import { isDate } from '../util/isDate';
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import { ObservableInput, OperatorFunction, SchedulerAction, SchedulerLike, TeardownLogic } from '../types';
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import { SimpleOuterSubscriber, innerSubscribe, SimpleInnerSubscriber } from '../innerSubscribe';
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/* tslint:disable:max-line-length */
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export function timeoutWith<T, R>(due: number | Date, withObservable: ObservableInput<R>, scheduler?: SchedulerLike): OperatorFunction<T, T | R>;
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/* tslint:enable:max-line-length */
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/**
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*
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* Errors if Observable does not emit a value in given time span, in case of which
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* subscribes to the second Observable.
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*
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* <span class="informal">It's a version of `timeout` operator that let's you specify fallback Observable.</span>
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*
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* 
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*
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* `timeoutWith` is a variation of `timeout` operator. It behaves exactly the same,
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* still accepting as a first argument either a number or a Date, which control - respectively -
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* when values of source Observable should be emitted or when it should complete.
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*
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* The only difference is that it accepts a second, required parameter. This parameter
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* should be an Observable which will be subscribed when source Observable fails any timeout check.
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* So whenever regular `timeout` would emit an error, `timeoutWith` will instead start re-emitting
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* values from second Observable. Note that this fallback Observable is not checked for timeouts
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* itself, so it can emit values and complete at arbitrary points in time. From the moment of a second
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* subscription, Observable returned from `timeoutWith` simply mirrors fallback stream. When that
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* stream completes, it completes as well.
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*
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* Scheduler, which in case of `timeout` is provided as as second argument, can be still provided
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* here - as a third, optional parameter. It still is used to schedule timeout checks and -
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* as a consequence - when second Observable will be subscribed, since subscription happens
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* immediately after failing check.
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*
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* ## Example
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* Add fallback observable
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* ```ts
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* import { interval } from 'rxjs';
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* import { timeoutWith } from 'rxjs/operators';
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*
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* const seconds = interval(1000);
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* const minutes = interval(60 * 1000);
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*
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* seconds.pipe(timeoutWith(900, minutes))
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* .subscribe(
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* value => console.log(value), // After 900ms, will start emitting `minutes`,
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* // since first value of `seconds` will not arrive fast enough.
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* err => console.log(err), // Would be called after 900ms in case of `timeout`,
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* // but here will never be called.
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* );
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* ```
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*
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* @param {number|Date} due Number specifying period within which Observable must emit values
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* or Date specifying before when Observable should complete
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* @param {Observable<T>} withObservable Observable which will be subscribed if source fails timeout check.
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* @param {SchedulerLike} [scheduler] Scheduler controlling when timeout checks occur.
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* @return {Observable<T>} Observable that mirrors behaviour of source or, when timeout check fails, of an Observable
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* passed as a second parameter.
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* @method timeoutWith
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* @owner Observable
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*/
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export function timeoutWith<T, R>(due: number | Date,
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withObservable: ObservableInput<R>,
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scheduler: SchedulerLike = async): OperatorFunction<T, T | R> {
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return (source: Observable<T>) => {
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let absoluteTimeout = isDate(due);
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let waitFor = absoluteTimeout ? (+due - scheduler.now()) : Math.abs(<number>due);
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return source.lift(new TimeoutWithOperator(waitFor, absoluteTimeout, withObservable, scheduler));
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};
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}
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class TimeoutWithOperator<T> implements Operator<T, T> {
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constructor(private waitFor: number,
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private absoluteTimeout: boolean,
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private withObservable: ObservableInput<any>,
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private scheduler: SchedulerLike) {
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}
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call(subscriber: Subscriber<T>, source: any): TeardownLogic {
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return source.subscribe(new TimeoutWithSubscriber(
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subscriber, this.absoluteTimeout, this.waitFor, this.withObservable, this.scheduler
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));
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}
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}
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/**
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* We need this JSDoc comment for affecting ESDoc.
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* @ignore
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* @extends {Ignored}
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*/
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class TimeoutWithSubscriber<T, R> extends SimpleOuterSubscriber<T, R> {
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private action?: SchedulerAction<TimeoutWithSubscriber<T, R>>;
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constructor(destination: Subscriber<T>,
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private absoluteTimeout: boolean,
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private waitFor: number,
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private withObservable: ObservableInput<any>,
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private scheduler: SchedulerLike) {
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super(destination);
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this.scheduleTimeout();
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}
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private static dispatchTimeout<T, R>(subscriber: TimeoutWithSubscriber<T, R>): void {
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const { withObservable } = subscriber;
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subscriber._unsubscribeAndRecycle();
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subscriber.add(innerSubscribe(withObservable, new SimpleInnerSubscriber(subscriber)));
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}
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private scheduleTimeout(): void {
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const { action } = this;
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if (action) {
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// Recycle the action if we've already scheduled one. All the production
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// Scheduler Actions mutate their state/delay time and return themeselves.
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// VirtualActions are immutable, so they create and return a clone. In this
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// case, we need to set the action reference to the most recent VirtualAction,
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// to ensure that's the one we clone from next time.
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this.action = (<SchedulerAction<TimeoutWithSubscriber<T, R>>> action.schedule(this, this.waitFor));
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} else {
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this.add(this.action = (<SchedulerAction<TimeoutWithSubscriber<T, R>>> this.scheduler.schedule<TimeoutWithSubscriber<T, R>>(
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TimeoutWithSubscriber.dispatchTimeout as any, this.waitFor, this
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)));
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}
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}
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protected _next(value: T): void {
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if (!this.absoluteTimeout) {
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this.scheduleTimeout();
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}
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super._next(value);
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}
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/** @deprecated This is an internal implementation detail, do not use. */
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_unsubscribe() {
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this.action = undefined;
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this.scheduler = null!;
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this.withObservable = null!;
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}
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}
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